#include<stdio.h>
#include<sys/types.h>
#include<unistd.h>

int main()
{
  pid_t id = fork();
  if(id == 0)
  {
    //child
    int count = 5;
    while(count)
    {
      printf("子进程正在运行：%d\n",count)
      sleep(1);
      count--;
    }
  }
  else
  {
    while(1)
    {
      printf("父进程正在运行.......\n");
      sleep(1);
    }
  }
   // while(1)
   // {
   //   printf("hello!\n");
   // }
  return 0;
}
